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What is the surge before death called?

Human brains show larger-than-life activity at moment of death

The brains of dying people may spark to sudden life in their final moments.

Two apparently brain-dead people taken off of life-support showed sudden spikes in neural activity, according to a study published on Monday.

The findings published in Proceedings of the National Academy of Sciences provide scientific support for accounts of “near-death experiences” — powerful and often mystical experiences that happen when a patient is about to die.

But they also shed new light into the surprisingly murky question of just how we die, said Jimo Borjigin of the University of Michigan.

In a small study of four patients taken off life support, Borjigin’s team found something surprising: the brains of two out of the four burst to life in the moments before death.

In particular, the patients displayed a sudden surge in the specific type of brain waves that usually indicate conscious thought.

Production of those brain waves — called gamma waves — spiked up to three hundred times in their previous levels in one patient in the moments before death.

That dying patient’s gamma wave patterns reached levels higher than those found in normal conscious brains.

The process our bodies and brains go through when we die remains poorly understood. In the conventional account, death is simply the sudden end of the processes of life — in particular, brain and heart activity.

For example, scientists don’t really understand what is happening on the inside when an apparently healthy person suffers a sudden trauma — like a car accident, fall or heart attack — and quickly dies.

“If you don’t know how exactly they die, how do you save them?” Borjigin asked

In practice, someone is legally dead when they are pronounced dead by a medical professional.

That professional doesn’t make that call based on a searching inventory of the patient’s subjective mental state — but based on the persistent absence of either a heartbeat or brain waves.

After a long period of such inactivity, family members often elect to disconnect a patient from breathing machines, at which point their body slowly dies from lack of oxygen.

But the recent findings suggest something more complex and harder to detect is going on. Borjigin points out there remains the possibility that a “covert consciousness” — a conscious experience we aren’t currently able to detect — continues below the surface, and springs to urgent life as death approaches.

That may be an adaptive response similar to the surge of cognitive activity that wakes a sleeping person (or, perhaps, a seal) with sleep apnea — in which the body stops breathing while asleep — in time to recover, Borjigin said.

“The brain has an extremely sensitive mechanism to sense oxygen levels in your body,” she said. “Even tiny drops of oxygen levels — the brain knows about that and constantly regulates the supply of oxygen.”

That goes against the idea of the brain as a passive passenger — which, Borjigin argues, makes sense.

“To think that when you are undergoing cardiac arrest — where the heart is stopping or not pumping blood — and the brain does nothing? It’s beyond me. The brain should be going crazy — which is exactly what happens,” she said.

Her next hypothesis is that “the brain drops everything else that is discretionary to focus on this essential function that is a survival, or self-resuscitation.”

This exploration of the inner territory of death is a far foray from Borjigin’s original area of specialization — circadian rhythms and the science of sleep.

In 2008, she was studying the impacts of stroke on the brain’s production of hormones that promote sleep, when she accidentally discovered something shocking.

In the moments right before death, the brains of the rats hooked up to their machines displayed a sudden surge in serotonin, a brain chemical deeply enmeshed in the processes of thought and sensing.

“Serotonin, as you probably know, is the essential neurotransmitter that’s important for brain functioning — which when it’s malfunctioning can leads to psychiatric disorders,” Borjigin told The Hill.

“So first thing I was thinking — ‘Wow. I wonder if the rats are having hallucinations?’”

Her second thought was that this serotonin surge was probably a well-understood phenomenon. She was wrong — both about that and the understanding of the general mechanics of dying. “I started looking into the literature, and I was surprised to find we know literally almost nothing.”

In the conventional understanding of death, the brain is a semi-passive passenger carried along by the heart — and which dies when the heart dies, Borjigin said.

There’s not much room in that model, however, for what Borjigin had found: a sudden surge of activity in dying brains. She built on those findings in a 2013 PNAS study that found that the brains of dying rats produced a surge of gamma waves — the pattern indicative of consciousness — as they experienced heart attacks.

“These data demonstrate that the mammalian brain can, albeit paradoxically, generate neural correlates of heightened conscious processing at near-death,” her team wrote in the 2013 paper.

That sentence contains an important caveat, and it is one that hangs over all this research. Dying rats may show “correlates” or traces of the activity that, in conscious mammals, is linked to coherent brain activity — but it’s so far impossible to know, subjectively, what dying rats or humans are experiencing.

Nonetheless, the 2013 paper, with its findings of surging brain activity in dying rats, made the New York Times. Its findings, the Times wrote, could “hold an explanation for the vivid, realistic visions experienced by some human victims of cardiac arrest” — visions reported by about 20 percent of heart attack patients.

These findings, Borjigin wrote at the time, could “explain why some individuals, during this state, can actually recall conversations happening in the operating room.”

These findings helped push Borjigin to the frontiers of consciousness research. Her sleep research focused on the pineal gland, a roughly almond-shaped organ under the forehead that releases the hormones that regulate sleep — and that many philosophical traditions have hypothesized as the seat of consciousness.

In 2013, Borjigin worked with Rick Strassman of the University of Mexico School of Medicine on a study that found the chemical dimethyltryptamine (DMT) — the active ingredient in the powerful Amazonian psychedelic ayahuasca — in the pineal glands of rats.

Strassman is a leading scientist who helped relaunch research into medical applications of psychedelics in the 1990s — sparking a renaissance in a field that medicine had largely turned away from since the 1970s.

Many of Strassman’s hypotheses — including that the brain releases a rush of DMT at death, a phenomenon he suggested could be related to end-of-life religious experiences — sit uneasily with the mainstream understanding of medicine.

But in 2019, Borjigin and Strassman found that dying rat brains released a surge of DMT as well.

That’s a strong indicator that human brains are doing something similar, Borjigin told an interviewer at the time — because cognitive phenomena found in rats usually display in people too, although not vice versa.

It’s hard to investigate much beyond that, however. The tests for a dying surge of DMT are highly invasive, and — absent end-of-life volunteers willing to have their skulls opened as they die in the name of science — very hard to corroborate.

And while the National Institutes of Health has poured money and attention over the past several years into the medical applications of psychedelics — particularly around curing depression or quitting dangerous drugs like alcohol or cigarettes — those studies largely focus on helping those who are unambiguously alive.

Also, “while psychedelic research has recently seen a renaissance, it’s mostly the use of psychedelics as a medicine or as a drug,” Borjigian added — rather than the study of how similar chemicals are produced and used by mammalian brains.

Since she began her studies on the cognitive life of the dying a decade ago, Borjigin hasn’t gotten a single NIH grant, she told The Hill.

“We definitely need to expand our studies, and we need NIH funders for these kinds of studies — to just study a lot more patients, maybe in a whole national network.”

That could lead to a reappraisal of the way the heart and brain work together to stave off the point of death — and therefore, potentially, to better understand their role in keeping us alive, Borjigin said.

Changes in the last hours and days — End of life care

What end of life care involves What to expect from end of life care Where you can be cared for Care at home Care in a care home Being cared for in hospital Hospice care Coping financially NHS continuing healthcare

Why plan ahead Advance statement about your wishes Advance decision to refuse treatment (living will) Lasting power of attorney

Coping with a terminal illness Managing pain and other symptoms Starting to talk about your illness Changes in the last hours and days Withdrawing treatment

Physical changes are likely to happen when you’re dying. These happen to most people during the terminal (dying) phase, whatever condition or illness they have. This can last hours or days.

Becoming drowsy

You’ll start to feel more tired and drowsy, and have less energy. You’ll probably spend more time sleeping, and as time goes on you’ll slip in and out of consciousness.

Not wanting to eat or drink

Not wanting to eat is common in people who are dying. You may also find it difficult to swallow medicine.

Your healthcare professionals can discuss alternative ways of taking medicine with you and your carers, if necessary.

Your family and carers may find it upsetting or worrying if you do not eat, especially if they see you losing weight, but they do not need to make you eat.

As you get closer to dying, your body will not be able to digest food properly and you will not need to eat.

If you cannot swallow to drink, your carers can wet your lips with water.

Changes in breathing

Your breathing may become less regular. You may develop Cheyne-Stokes breathing, when periods of shallow breathing alternate with periods of deeper, rapid breathing.

The deep, rapid breathing may be followed by a pause before breathing begins again.

Your breathing may also become more noisy as a result of the build-up of mucus.

The body naturally produces mucus in your breathing system, including the lungs and nasal passages. When you’re healthy, this mucus is removed through coughing.

When you’re dying and no longer moving around, the mucus can build up and cause a rattling sound when you breathe.

Confusion and hallucinations

Medicines or changes in the chemical balance of your brain can cause confusion or hallucinations.

A hallucination is when you see or hear things that are not there. If you become confused, you may not recognise where you are or the people you’re with.

Some people may be restless or seem to be in distress. For example, they may want to move about, even though they are not able to get out of bed, or they may shout or lash out.

This can be out of character and distressing for family and carers.

The medical team can rule out or treat any underlying causes, such as pain, breathing problems or infection, or calm the person who is dying.

If no underlying cause can be identified, there are medicines that can ease distress.

Cold hands and feet

Your feet and hands may feel cold because of changes in your circulation. Blankets over your hands and feet can keep you warm.

Your skin may look slightly blue because of a lack of oxygen in your blood. This is known as cyanosis.

More information

Find more information about the last hours and days of life, including advice for carers and relatives.

  • Helix Centre: What you can do to practically care for someone who is in their last days and hours of life (PDF, 210kb)
  • Dying Matters: Being with someone when they die
  • Marie Curie: What to expect in the last weeks and days
  • Marie Curie: Final moments of life
  • Cancer Research UK: Final days
  • coping with a terminal illness
  • what to expect from end of life care
  • why and how you can plan ahead

Page last reviewed: 15 October 2020
Next review due: 15 October 2023

Terminal lucidity

Terminal lucidity, also known as paradoxical lucidity, rallying or the rally, is an unexpected return of mental clarity and memory, or suddenly regained consciousness that occurs in the time shortly before death in patients with severe psychiatric or neurological disorders. [1] [2] [3] This condition has been reported by physicians since the 19th century.

History [ edit ]

Several case reports in the 19th century described the unusual condition of an improvement and recovery of the mental state in patients days or weeks before death. William Munk, for instance, in 1887 called the phenomenon «lucidity before death». [4] According to historical reviews headed by the biologist Michael Nahm, who also has an interest in mediumship and near-death experiences, [5] the phenomena have been noted in patients with diseases which cause progressive cognitive impairment, such as Alzheimer’s disease, but also schizophrenia, tumors, strokes, meningitis, and Parkinson’s disease. [6] [7] [8] However, terminal lucidity is not currently listed as a medical term. [9]

According to Nahm, it may be present even in cases of patients with previous mental disability. [10] Nahm defines two subtypes: one that comes gradually (a week before death), and another that comes rapidly (hours before death), with the former occurring more often than the latter. There may be plenty of cases reported in literature, although the phrase terminal lucidity was coined in 2009. [11] Interest in this condition, which dwindled during the 20th century, has been reignited by further studies. [4] A 2020 research screened for what the authors preferred to call «paradoxical lucidity», a general term for unexpected remissions in dementias, independent of whether it followed a terminality process or not; it found strong association of the condition as a near-death phenomenon and stated that it can overlap the concept of «terminal lucidity» in some cases. [6] Such a paradoxical condition is considered a challenge to the irreversibility paradigm of chronic degenerative dementias such as Alzheimer’s. [12]

Causes [ edit ]

The earliest attempt at explanation was issued by Benjamin Rush in 1812, which proposed the hypothesis that a reawakening could be due to a nervous excitation caused by pain or fever, or else because of dead blood vessels, released by a leakage of water in the brain chambers. Johannes Friedreich, in 1839, proposed that the factors causing impairments may be reversed shortly before death, analogous to the reabsorption in terminal patients with hydrocephalus, and that high fever may be a cause of it. According to Macleod (2009) [13] in his observations, explanative causes could not be found for the variety of cases, but it was suggested that due to the modern pharmacology in terminal cases, the condition may be less common today. [4] A recent proposed mechanism includes a non-tested hypothesis of neuromodulation, according to which near-death discharges of neurotransmitters and corticotropin-releasing peptides act upon preserved circuits of the medial prefrontal cortex and hippocampus, promoting memory retrieval and mental clarity. [14]

References [ edit ]

  1. ^ Koczanowicz, Leszek (2020). «Chapter 12 — The Anxiety of Clairvoyance: Terminal Lucidity and the End of Culture». Anxiety and Lucidity: Reflections on Culture in Times of Unrest. Routledge. pp. 162–198. ISBN978-0367218232 .
  2. ^
  3. Mendoza, Marilyn A. «Why Some People Rally for One Last Goodbye Before Death». Psychology Today (blog) . Retrieved 26 August 2019 .
  4. ^
  5. Bursack, Carol Bradley. «When Loved Ones Rally Before Death». AgingCare . Retrieved 26 August 2019 .
  6. ^ abc
  7. Chiriboga-Oleszczak, Boris Alejandro (2017-03-28). «Terminal lucidity». Current Problems of Psychiatry. 18 (1): 34–46. doi: 10.1515/cpp-2017-0003 . ISSN2353-8627.
  8. ^Michael Nahm
  9. ^ ab
  10. Batthyány, Alexander; Greyson, Bruce (2020-08-27). «Spontaneous remission of dementia before death: Results from a study on paradoxical lucidity». Psychology of Consciousness: Theory, Research, and Practice. 8: 1–8. doi:10.1037/cns0000259. ISSN2326-5531. S2CID225192667.
  11. ^
  12. Nahm, Michael; Greyson, Bruce (December 2009). «Terminal lucidity in patients with chronic schizophrenia and dementia: a survey of the literature». Journal of Nervous and Mental Disease. 197 (12): 942–944. doi:10.1097/NMD.0b013e3181c22583. ISSN1539-736X. PMID20010032.
  13. ^
  14. Nahm, Michael; Greyson, Bruce; Kelly, Emily Williams; Haraldsson, Erlendur (July–August 2012). «Terminal lucidity: a review and a case collection». Archives of Gerontology and Geriatrics. 55 (1): 138–142. doi:10.1016/j.archger.2011.06.031. ISSN1872-6976. PMID21764150.
  15. ^Webster Medical Dictionary
  16. ^
  17. Nahm, M.; Greyson, B. (2014). «The Death of Anna Katharina Ehmer: A Case Study in Terminal Lucidity». OMEGA. 68 (1): 77–87. doi:10.2190/OM.68.1.e. PMID24547666. S2CID1265185.
  18. ^
  19. Bering, Jesse (2017). «One Last Goodbye: The Strange Case of Terminal Lucidity». Scientific American Blog Network.
  20. ^
  21. Mashour, George A.; Frank, Lori; Batthyany, Alexander; Kolanowski, Ann Marie; Nahm, Michael; Schulman-Green, Dena; Greyson, Bruce; Pakhomov, Serguei; Karlawish, Jason; Shah, Raj C. (2019-06-19). «Paradoxical lucidity: A potential paradigm shift for the neurobiology and treatment of severe dementias». Alzheimer’s & Dementia. 15 (8): 1107–1114. doi: 10.1016/j.jalz.2019.04.002 . ISSN1552-5260. PMID31229433.
  22. ^
  23. Macleod, AD (December 2009). «Lightening up before death». Palliative & Supportive Care. 7 (4): 513-516. doi:10.1017/S1478951509990526. PMID19939314.
  24. ^
  25. Bostanciklioğlu, Mehmet (January 2021). «Unexpected awakenings in severe dementia from case reports to laboratory». Alzheimer’s & Dementia. 17 (1): 125–136. doi:10.1002/alz.12162. ISSN1552-5279. PMID33064369. S2CID222840626.

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  • Medical aspects of death
  • Dementia
  • Mental states
  • 19th century in medicine
  • 2009 neologisms
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